The present invention relates to an intraoral sensor design to be applicable to radiographic imaging sensors such as film, storage phosphor devices or solid-state direct capture devices (e.g. CCD's or CMOS based devices) or any other imaging sensor that can be used to produce radiographic images. Such sensors may be components of radiographic imaging systems that may include computers and video monitors for displaying radiographs. The present invention is also directed toward a method of correcting distortions appearing in the images of such radiographic imaging systems caused by the non-perpendicularity of the x-ray source relative to the imaging surface. Such analyses may be performed on a PC, which in turn may be part of a digital radiographic imaging system. The illuminating x-ray radiation source for such sensors and radiographic imaging systems is not the subject of the present invention.
Radiographs are fundamental to most dental diagnostic procedures. However, a common complaint and problem during radiographic exams is patient discomfort during the placement of radiographic sensors within the mouth. The majority of these complaints involve the placement of the radiographic sensor in the posterior maxillary and mandibular arches of the patient. This problem is primarily due to the limited space available for proper placement of the sensors within these regions. This has been a problem since the inception of dental radiography using standard x-ray film technology.
A common method used to reduce such patient discomfort is to bend portions of the film package to conform to the anatomic shape of the mandibular or maxillary arches. However this bending contributes to the problems of image distortion of the intended subject as described below.
Recently, solid-state x-ray sensors have been developed that replace film. The patient discomfort problem for these sensors is even greater because these devices are rigid by nature and cannot be bent like film. With these rigid sensors, the only recourse is to place the sensor at a more comfortable angle and position for the patient, but such positioning is normally not optimal for a diagnostic radiograph of the intended subject. One study has shown that using such rigid devices results in more sensor placement errors than conventional film, thus requiring more retakes to produce clinically acceptable radiographs (C.H. Versteeg, et. al., An evaluation of periapical radiology with a charge-coupled device, Dentomaxillofacial Radiology, 1998, 27: 97-101).
Both of these approaches, using film and rigid sensors, result in a distorted radiographic image of the intended subject when the x-ray beam is not perpendicular to the imaging plane.
Thus, a need exists to provide for a more comfortable sensor configuration while correcting for the projective distortions of the images produced when the x-ray beam is not perpendicular to the imaging plane.